first strike
From Longman Dictionary of Contemporary EnglishRelated topics: Militaryfirst strikeˌfirst ˈstrike noun [countable] PMWARan attack made on your enemy before they attack you, especially an attack made using nuclear weaponsExamples from the Corpusfirst strike• The reason he survived the first strike is the reason that you all escaped the second.• There was a caretaker here, in the basement, when the first strike occurred.